Just to close this discussion, seller would not cooperate on any work or price adjustment to address the exhaust manifold leak. With many unknown concerns about the engines I had to pass. Sad. I loved that boat.
Went ahead and bought the Jefferson with frickin’ Volvo 72s.
I’m so gonna miss my Cummins and all the great info and feedback on this forum.
It’ll be a big learning curve again.
Will you guys still talk to me if I post?
Thanks for the info Larry. What props do you have and how much adjustment (pitch, diameter) was made to get the specs you wanted?
Thanks again Tony. So if I make sure to prop to 18.6 GPH or below at 2000 rpm before the manifolds are fixed then I might avoid this in future? Is that advice still accurate and recommended?
OK, got some more pics to confirm the exhaust leak. I should have had a better light. So question now is, do I have to fix it?
And if coolers are coming off anyway, does that make the job much more straightforward or is there a lot of other dismantling to do to access the manifolds?
And is that turbo been heated up way too much?
Thanks in advance….
No more pics. My camera battery died at a critical moment of all things!
Thanks Tony for the prompt reply. I will take this opinion into account. Around the lifting eye it was discolored a little black in spots but not “sooty”. It was like baked on dirt. Is that the sign?
That sounds pretty reasonable. Certainly better than the jacketed doomed to fail ones that cost about $4500 from Cummins the last time I checked. Thanks again for all the good advice.
Corey,
Thanks again for helping me assess this Volvo engine exhaust design. I have read pretty well all the Tony’s Tips on the exhaust issue and you have confirmed for me that all these “deAngelo” style double walled elbows, while nice to look at and easy to fit are doomed. I guess the only way to rationalize it when buying a boat with this setup is to accept that a new exhaust system has to be installed. In the pictures you provided, can you give me a ballpark number on cost per side for that design?
Regarding the throttles electronic vs. manual, I am not where the boat is situated any more so cannot get the info you require. We will have to leave that for now.
I had a similar issue. FWIW after much ado it was the Sea Fire (Fireboy) module failing. If you have one of those extinguishers, try bypassing it and see if the problem remains.
Thanks again Corey. There is what I assume to be a muffler. See the YW listing here. There are photos of the mufflers. Maybe you can figure it out.
https://www.yachtworld.com/boats/1998/Jefferson-48-Rivanna-3204386/Jacksonville/FL/United-States?refSource=standard%20listing#.WzlyyNJKiUl
I don’t know about the ECM. All I can tell is that the throttle cables terminate at some sort of electronic module under the dash at the helm and I cannot see any throttle cables attached to the engines. The gauges are all analog with no display for fuel economy, or anything. I need someone who knows about these things to explain it to me.
Corey, thanks for the reply. I don’t know for sure but if I had to guess, judging by how I remember the position of the the deck drain overflow fittings, I think there would be about 18″ or more. It’s a big engine room.
Finally solved this one. When the genny started behaving the same way as the mains- start but won’t run, it led us to the Sea-Fire Halon control module. When bypassed, genny started and ran fine. Replaced the module. Everything good now. Thanks for the help guys.
My props are actually Michigan Hy Torq MY-T4, not the Dyna Quad I mentioned in the previous post. I’m not sure what difference that makes but they were recommended for a Sea Ray.
I very much appreciate the response Tony. I was hoping to discover that I am close to what is expected. My props are Michigan Wheel Dyna Quad Nibral 22×21 with Light Cup (which Michigan said Sea Ray uses). I bought them new after bending my old props from 22X24 to 22X22 and still only getting 2650 rpm at WOT. I expected another 50-60 RPM going to 22X21 (to get over the magical 2700 number) but lo and behold, no change. Is it the cup that prevents what I expected?
The boat does seem to pop up on and hold plane nicely though and if all the parameters look good I will stick with them.
My boat is dry weight 30,000 but when on the travel lift it clocks in at 38,000. Man that “stuff” adds up!
The .57 is Nautical MPG so I will be content with that.
Any further comments are welcome.
I installed a Noland MD33 for dual engine analog (directly from the analog gauges) to NMEA 2000 conversion on my mains and a Noland RS-11 in the engine room to send gauge data from my generator and turbo boost sender to the NMEA 2000. Works great. It requires some fiddling around to calibrate but once you get the hang of it it works very well.
Rob,
Thanks very much for these diagrams. I spent a few hours today identifying wires, freshening up a bunch of negative buss bars and engine connections thinking that a common neutral location is the likeliest cause of the problem affecting both engines . One engine connection to the main buss bar was not as tight as I would expect. I will see what happens going forward.
The connectors I could access looked great when unplugged. So many wires disappear into the nether regions of the boat though so this may beat me. Would a Cummins service tech ever know something about an issue like this or have some sort of diagnostic process or is it a needle in a haystack for him too?
I disabled my air heaters a while ago by just removing the main hot wire coming from the starter post to the wire harness. Something still clicks (relay?) in the assembly though when the start engine button is clicked to the run position (not start). Could this have some affect on this problem?
Boy, don’t I know it. I have no idea what Sea Ray was thinking with this design. I’m a raw rookie at all this but have Ā discovered enough to know it’s better to do the work myself than find out the guy I paid only went half way because it was too uncomfortable. Thanks for the support.
There are no shut off valves and it is so tight between the top of the tank and the floor above it would be a skin ripping experience to free the lines I’d rather avoid. If the problem can be resolved by running off some fuel, I will just wait until I have 1/2 full tanks. Thanks for the information Rob.
I finally got around to disconnecting the return fuel line on the “easy” side. After about a pint of fuel squirted out I had to abandon the mission and reconnect. Is it possible I am siphoning fuel back from my tank since I just filled up? i.e. the return line going into the tank has a fitting that projects far enough into the tank to be submerged?
Thanks so much for this advice Tony. I can just keep doing what I am already by the sounds of it. That was my gut instinct as well.
Jerome
